围垦对东海农场沉积物无机氮分布的影响

Effect of reclamation on the distribution of inorganic nitrogen in sediments from Donghai beach

选择了上海滨岸东海农场剖面作为研究对象 ,通过对其表层沉积物及柱状沉积物的取样和化学分析 ,结果表明 :表层沉积物中无机氮以NH4 N为主 ,11月份NH4 N和NO3 N含量显著增加 ,大大超过 8月和 2月 ;围垦前与围垦后 (过程中 )的无机氮具有一致的分布序列 :NH4 N >NO3 N >>NO2 N ,并且围垦后 (过程中 )无机氮含量有增加的趋势 ;不同地貌单元沉积物中无机氮的含量发生变化 ,由围垦前的高潮滩 >中潮滩 >低潮滩变为围垦后 (过程中 )的低潮滩 >高潮滩 >中潮滩 ;围垦后 (过程中 )柱状沉积物中NH4 N和NO3

Based on the analysis on surface sediments and core sediments taken from selected Donghai beach, the results shown that NH 4 N was dominant in inorganic nitrogen in surface sediments, the concentration levels of NH 4 N and NO 3 N on November were increased obviously compared with February and August. Inorganic nitrogen concentration was similar before and after reclamation in order NH 4 N>NO 3 N>>NO 2 N, but was characterized by high inorganic nitrogen concentration levels after reclamation. The concentration of NH 4 N changed from high tidal flat to middle tidal flat, and to low tidal flat before reclamation, while from low tidal flat to high tidal flat, and to middle tidal flat after reclamation in different geomorphologic positions. After reclamation, the changing trend of NH 4 N and NO 3 N concentrations in core profiles transformed from increase with the increasing depth to decrease with the increasing depth.